(1) Field Of The Invention
This invention relates to a mechanism for the opening and closing of a passageway in the hull of a submarine vehicle and in particular, to an elastomeric shutter mechanism.
(2) Description of the Prior Art
Closable openings are necessary in the hull of a submarine vessel for the ejection of weapons, Unmanned Undersea Vehicles (UUV), countermeasures, waste and water and for the ingestion of water and (UUV) into the submarine. Typically, the openings on submarine hulls have steel doors and opening mechanisms to allow for ejection and ingestion to and from the submarine hull. One example of a prior art opening mechanism in a submarine hull is a torpedo launchway shutter door and ejection pump sea chest inlet.
However, such prior art opening mechanisms have many disadvantages. Firstly, the mechanism which operates the steel doors is expensive to fabricate. Secondly, the installation and maintenance of the door and opening mechanism is expensive. Thirdly, the prior art mechanism causes excessive noise because of fluid flow through gaps around the openings and rattles caused by the mechanical parts of the mechanism.
Other prior art closure mechanisms for missiles and rockets include frangible diaphragms or covers which can be made of plastic or an elastomeric material are disclosed in U.S. Pat. Nos. 3,135,163; 3,279,319; 4,301,708; 4,498,368 and 5,062,345. Such frangible closures, however, are not a feasible alternative because they are destroyed upon launching the projectile or missile.
Accordingly, what is needed is a shutter mechanism which is made from a molded elastomeric material and which can be fabricated and installed at a lower cost than the prior art steel door mechanism. Such an elastomeric shutter mechanism must be able to be sealed closed and have a simple retraction mechanism to eliminate rattles and excessive noise. Finally, the elastomeric shutter mechanism must be able to be used repeatedly and return to its original form when closed.